The disposal of waste is a serious problem to governments, especially municipal governments. The waste disposal process is regulated by increasingly stricter standards since some wastes are toxic. In the case of industrial waste, there are even more problematic materials, such as petrochemicals, PCBs (polychlorinated biphenyls), etc. than in common, non-industrial waste. Additionally, medical and other biological waste is often hazardous and requires complete sterilization and decomposition.
Previously, other methods of waste disposal were more attractive than incineration. Landfills, for example, were used instead of incineration since the cost of disposing waste at a landfill was far less than that of incineration. However, increasingly more severe environmental standards have made landfills less attractive, primarily because of the increased awareness that toxic chemicals, over long periods of time, percolate through the ground contaminating aquifers. Similarly, the ever increasing quantity of waste make landfills and other methods physically impractical.
Accordingly, destructive, degradative processes such as incineration have become more popular. Destructive techniques like incineration must efficiently turn waste into innocuous end-products. This is a particularly acute problem in incineration where burning hazardous waste requires high temperatures so that the resulting decomposition products are environmentally benign. The high temperatures needed and the large quantities of waste involved require the development of incinerators that are economically and environmentally efficient. The emissions from such products are generally gaseous and must comply with standards set by international and governmental agencies. Similarly, solid and particulate wastes of incineration, such as slag, bottom ash and fly ash, must be neutered to remove harmful effects to the environment.
Examples of recently proposed incineration methods and incinerators can be found in U.S. Pat. Nos. 5,752,452 and 5,179,903, and WO 96/24804, Abboud. U.S. Pat. No. 5,179,903 and WO 96/24804 describe recycled flue gases which are augmented with oxygen, U.S. Pat. No. 5,752,452 describes a system with lances which inject oxygen into a heating zone at a velocity of at least 350 ft/sec.
However, despite improvements in incinerators and incineration processes, capital and maintenance costs are still very high. In addition, effluents emitted into the environment still require further reduction.